$ { \left[\begin{array}{rrr}{1} & {2} & {4} \\ {3} & {4} & {4}\end{array}\right]-\left[\begin{array}{rrr}{4} & {2} & {-1} \\ {0} & {3} & {0}\end{array}\right] = {?} } $
Explanation: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{1}-{4} & {2}-{2} & {4}-{-1} \\ {3}-{0} & {4}-{3} & {4}-{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{-3} & {0} & {5} \\ {3} & {1} & {4}\end{array}\right]}$